Peracetic acid effects on human bronchial cells in an air liquid interface

Peracetic acid (PAA) is utilized as an industrial disinfectant for cleaning and sterilization of water infrastructure, food-safe machinery, surgical implements, and more. PAA typically exists as a mixture with hydrogen peroxide, acetic acid, water, and oxygen. These PAA cleaning solutions have been increasingly implemented in occupational settings due to their environmentally friendly decomposition products but the strong oxidative potential that allows them to effectively sanitize surfaces also underlies their ability to damage human airways. PAA mixtures are regarded as an asthmagen and occupational exposure has been associated with acute asthma-like symptoms such as airway and mucosal irritation, cough, wheeze, and shortness of breath. To evaluate the broad effects of PAA vapor exposure to human bronchial cells in vitro, normal human bronchial epithelial (NHBE) cells were cultured at the air-liquid interface (ALI) and exposures were conducted to PAA vapors during a four-hour exposure window at four concentrations: 0, 3, 12, and 24 ppm. Cells were allowed to recover for four and twenty-four hours to capture a spectrum of post-exposure response. Data was gathered for cytotoxicity, viability, cell layer integrity (via transepithelial electrical resistance measurements and qualitative histological observations), and protein response for proinflammatory mediators Endothelin-1 (ET-1), Interleukin-6 (IL-6), and Interleukin-8 (IL-8).